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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IOMMU API for s390 PCI devices
4 *
5 * Copyright IBM Corp. 2015
6 * Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
7 */
8
9#include <linux/pci.h>
10#include <linux/iommu.h>
11#include <linux/iommu-helper.h>
12#include <linux/sizes.h>
13#include <linux/rculist.h>
14#include <linux/rcupdate.h>
15#include <asm/pci_dma.h>
16
17static const struct iommu_ops s390_iommu_ops;
18
19struct s390_domain {
20 struct iommu_domain domain;
21 struct list_head devices;
22 unsigned long *dma_table;
23 spinlock_t list_lock;
24 struct rcu_head rcu;
25};
26
27static struct s390_domain *to_s390_domain(struct iommu_domain *dom)
28{
29 return container_of(dom, struct s390_domain, domain);
30}
31
32static bool s390_iommu_capable(struct device *dev, enum iommu_cap cap)
33{
34 switch (cap) {
35 case IOMMU_CAP_CACHE_COHERENCY:
36 return true;
37 case IOMMU_CAP_INTR_REMAP:
38 return true;
39 default:
40 return false;
41 }
42}
43
44static struct iommu_domain *s390_domain_alloc(unsigned domain_type)
45{
46 struct s390_domain *s390_domain;
47
48 if (domain_type != IOMMU_DOMAIN_UNMANAGED)
49 return NULL;
50
51 s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
52 if (!s390_domain)
53 return NULL;
54
55 s390_domain->dma_table = dma_alloc_cpu_table();
56 if (!s390_domain->dma_table) {
57 kfree(s390_domain);
58 return NULL;
59 }
60 s390_domain->domain.geometry.force_aperture = true;
61 s390_domain->domain.geometry.aperture_start = 0;
62 s390_domain->domain.geometry.aperture_end = ZPCI_TABLE_SIZE_RT - 1;
63
64 spin_lock_init(&s390_domain->list_lock);
65 INIT_LIST_HEAD_RCU(&s390_domain->devices);
66
67 return &s390_domain->domain;
68}
69
70static void s390_iommu_rcu_free_domain(struct rcu_head *head)
71{
72 struct s390_domain *s390_domain = container_of(head, struct s390_domain, rcu);
73
74 dma_cleanup_tables(s390_domain->dma_table);
75 kfree(s390_domain);
76}
77
78static void s390_domain_free(struct iommu_domain *domain)
79{
80 struct s390_domain *s390_domain = to_s390_domain(domain);
81
82 rcu_read_lock();
83 WARN_ON(!list_empty(&s390_domain->devices));
84 rcu_read_unlock();
85
86 call_rcu(&s390_domain->rcu, s390_iommu_rcu_free_domain);
87}
88
89static void __s390_iommu_detach_device(struct zpci_dev *zdev)
90{
91 struct s390_domain *s390_domain = zdev->s390_domain;
92 unsigned long flags;
93
94 if (!s390_domain)
95 return;
96
97 spin_lock_irqsave(&s390_domain->list_lock, flags);
98 list_del_rcu(&zdev->iommu_list);
99 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
100
101 zpci_unregister_ioat(zdev, 0);
102 zdev->s390_domain = NULL;
103 zdev->dma_table = NULL;
104}
105
106static int s390_iommu_attach_device(struct iommu_domain *domain,
107 struct device *dev)
108{
109 struct s390_domain *s390_domain = to_s390_domain(domain);
110 struct zpci_dev *zdev = to_zpci_dev(dev);
111 unsigned long flags;
112 u8 status;
113 int cc;
114
115 if (!zdev)
116 return -ENODEV;
117
118 if (WARN_ON(domain->geometry.aperture_start > zdev->end_dma ||
119 domain->geometry.aperture_end < zdev->start_dma))
120 return -EINVAL;
121
122 if (zdev->s390_domain)
123 __s390_iommu_detach_device(zdev);
124 else if (zdev->dma_table)
125 zpci_dma_exit_device(zdev);
126
127 cc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
128 virt_to_phys(s390_domain->dma_table), &status);
129 /*
130 * If the device is undergoing error recovery the reset code
131 * will re-establish the new domain.
132 */
133 if (cc && status != ZPCI_PCI_ST_FUNC_NOT_AVAIL)
134 return -EIO;
135 zdev->dma_table = s390_domain->dma_table;
136
137 zdev->dma_table = s390_domain->dma_table;
138 zdev->s390_domain = s390_domain;
139
140 spin_lock_irqsave(&s390_domain->list_lock, flags);
141 list_add_rcu(&zdev->iommu_list, &s390_domain->devices);
142 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
143
144 return 0;
145}
146
147static void s390_iommu_detach_device(struct iommu_domain *domain,
148 struct device *dev)
149{
150 struct zpci_dev *zdev = to_zpci_dev(dev);
151
152 WARN_ON(zdev->s390_domain != to_s390_domain(domain));
153
154 __s390_iommu_detach_device(zdev);
155 zpci_dma_init_device(zdev);
156}
157
158static void s390_iommu_get_resv_regions(struct device *dev,
159 struct list_head *list)
160{
161 struct zpci_dev *zdev = to_zpci_dev(dev);
162 struct iommu_resv_region *region;
163
164 if (zdev->start_dma) {
165 region = iommu_alloc_resv_region(0, zdev->start_dma, 0,
166 IOMMU_RESV_RESERVED, GFP_KERNEL);
167 if (!region)
168 return;
169 list_add_tail(®ion->list, list);
170 }
171
172 if (zdev->end_dma < ZPCI_TABLE_SIZE_RT - 1) {
173 region = iommu_alloc_resv_region(zdev->end_dma + 1,
174 ZPCI_TABLE_SIZE_RT - zdev->end_dma - 1,
175 0, IOMMU_RESV_RESERVED, GFP_KERNEL);
176 if (!region)
177 return;
178 list_add_tail(®ion->list, list);
179 }
180}
181
182static struct iommu_device *s390_iommu_probe_device(struct device *dev)
183{
184 struct zpci_dev *zdev;
185
186 if (!dev_is_pci(dev))
187 return ERR_PTR(-ENODEV);
188
189 zdev = to_zpci_dev(dev);
190
191 if (zdev->start_dma > zdev->end_dma ||
192 zdev->start_dma > ZPCI_TABLE_SIZE_RT - 1)
193 return ERR_PTR(-EINVAL);
194
195 if (zdev->end_dma > ZPCI_TABLE_SIZE_RT - 1)
196 zdev->end_dma = ZPCI_TABLE_SIZE_RT - 1;
197
198 return &zdev->iommu_dev;
199}
200
201static void s390_iommu_release_device(struct device *dev)
202{
203 struct zpci_dev *zdev = to_zpci_dev(dev);
204
205 /*
206 * release_device is expected to detach any domain currently attached
207 * to the device, but keep it attached to other devices in the group.
208 */
209 if (zdev)
210 __s390_iommu_detach_device(zdev);
211}
212
213static void s390_iommu_flush_iotlb_all(struct iommu_domain *domain)
214{
215 struct s390_domain *s390_domain = to_s390_domain(domain);
216 struct zpci_dev *zdev;
217
218 rcu_read_lock();
219 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
220 zpci_refresh_trans((u64)zdev->fh << 32, zdev->start_dma,
221 zdev->end_dma - zdev->start_dma + 1);
222 }
223 rcu_read_unlock();
224}
225
226static void s390_iommu_iotlb_sync(struct iommu_domain *domain,
227 struct iommu_iotlb_gather *gather)
228{
229 struct s390_domain *s390_domain = to_s390_domain(domain);
230 size_t size = gather->end - gather->start + 1;
231 struct zpci_dev *zdev;
232
233 /* If gather was never added to there is nothing to flush */
234 if (!gather->end)
235 return;
236
237 rcu_read_lock();
238 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
239 zpci_refresh_trans((u64)zdev->fh << 32, gather->start,
240 size);
241 }
242 rcu_read_unlock();
243}
244
245static void s390_iommu_iotlb_sync_map(struct iommu_domain *domain,
246 unsigned long iova, size_t size)
247{
248 struct s390_domain *s390_domain = to_s390_domain(domain);
249 struct zpci_dev *zdev;
250
251 rcu_read_lock();
252 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
253 if (!zdev->tlb_refresh)
254 continue;
255 zpci_refresh_trans((u64)zdev->fh << 32,
256 iova, size);
257 }
258 rcu_read_unlock();
259}
260
261static int s390_iommu_validate_trans(struct s390_domain *s390_domain,
262 phys_addr_t pa, dma_addr_t dma_addr,
263 unsigned long nr_pages, int flags)
264{
265 phys_addr_t page_addr = pa & PAGE_MASK;
266 unsigned long *entry;
267 unsigned long i;
268 int rc;
269
270 for (i = 0; i < nr_pages; i++) {
271 entry = dma_walk_cpu_trans(s390_domain->dma_table, dma_addr);
272 if (unlikely(!entry)) {
273 rc = -ENOMEM;
274 goto undo_cpu_trans;
275 }
276 dma_update_cpu_trans(entry, page_addr, flags);
277 page_addr += PAGE_SIZE;
278 dma_addr += PAGE_SIZE;
279 }
280
281 return 0;
282
283undo_cpu_trans:
284 while (i-- > 0) {
285 dma_addr -= PAGE_SIZE;
286 entry = dma_walk_cpu_trans(s390_domain->dma_table,
287 dma_addr);
288 if (!entry)
289 break;
290 dma_update_cpu_trans(entry, 0, ZPCI_PTE_INVALID);
291 }
292
293 return rc;
294}
295
296static int s390_iommu_invalidate_trans(struct s390_domain *s390_domain,
297 dma_addr_t dma_addr, unsigned long nr_pages)
298{
299 unsigned long *entry;
300 unsigned long i;
301 int rc = 0;
302
303 for (i = 0; i < nr_pages; i++) {
304 entry = dma_walk_cpu_trans(s390_domain->dma_table, dma_addr);
305 if (unlikely(!entry)) {
306 rc = -EINVAL;
307 break;
308 }
309 dma_update_cpu_trans(entry, 0, ZPCI_PTE_INVALID);
310 dma_addr += PAGE_SIZE;
311 }
312
313 return rc;
314}
315
316static int s390_iommu_map_pages(struct iommu_domain *domain,
317 unsigned long iova, phys_addr_t paddr,
318 size_t pgsize, size_t pgcount,
319 int prot, gfp_t gfp, size_t *mapped)
320{
321 struct s390_domain *s390_domain = to_s390_domain(domain);
322 size_t size = pgcount << __ffs(pgsize);
323 int flags = ZPCI_PTE_VALID, rc = 0;
324
325 if (pgsize != SZ_4K)
326 return -EINVAL;
327
328 if (iova < s390_domain->domain.geometry.aperture_start ||
329 (iova + size - 1) > s390_domain->domain.geometry.aperture_end)
330 return -EINVAL;
331
332 if (!IS_ALIGNED(iova | paddr, pgsize))
333 return -EINVAL;
334
335 if (!(prot & IOMMU_READ))
336 return -EINVAL;
337
338 if (!(prot & IOMMU_WRITE))
339 flags |= ZPCI_TABLE_PROTECTED;
340
341 rc = s390_iommu_validate_trans(s390_domain, paddr, iova,
342 pgcount, flags);
343 if (!rc)
344 *mapped = size;
345
346 return rc;
347}
348
349static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
350 dma_addr_t iova)
351{
352 struct s390_domain *s390_domain = to_s390_domain(domain);
353 unsigned long *rto, *sto, *pto;
354 unsigned long ste, pte, rte;
355 unsigned int rtx, sx, px;
356 phys_addr_t phys = 0;
357
358 if (iova < domain->geometry.aperture_start ||
359 iova > domain->geometry.aperture_end)
360 return 0;
361
362 rtx = calc_rtx(iova);
363 sx = calc_sx(iova);
364 px = calc_px(iova);
365 rto = s390_domain->dma_table;
366
367 rte = READ_ONCE(rto[rtx]);
368 if (reg_entry_isvalid(rte)) {
369 sto = get_rt_sto(rte);
370 ste = READ_ONCE(sto[sx]);
371 if (reg_entry_isvalid(ste)) {
372 pto = get_st_pto(ste);
373 pte = READ_ONCE(pto[px]);
374 if (pt_entry_isvalid(pte))
375 phys = pte & ZPCI_PTE_ADDR_MASK;
376 }
377 }
378
379 return phys;
380}
381
382static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
383 unsigned long iova,
384 size_t pgsize, size_t pgcount,
385 struct iommu_iotlb_gather *gather)
386{
387 struct s390_domain *s390_domain = to_s390_domain(domain);
388 size_t size = pgcount << __ffs(pgsize);
389 int rc;
390
391 if (WARN_ON(iova < s390_domain->domain.geometry.aperture_start ||
392 (iova + size - 1) > s390_domain->domain.geometry.aperture_end))
393 return 0;
394
395 rc = s390_iommu_invalidate_trans(s390_domain, iova, pgcount);
396 if (rc)
397 return 0;
398
399 iommu_iotlb_gather_add_range(gather, iova, size);
400
401 return size;
402}
403
404int zpci_init_iommu(struct zpci_dev *zdev)
405{
406 int rc = 0;
407
408 rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL,
409 "s390-iommu.%08x", zdev->fid);
410 if (rc)
411 goto out_err;
412
413 rc = iommu_device_register(&zdev->iommu_dev, &s390_iommu_ops, NULL);
414 if (rc)
415 goto out_sysfs;
416
417 return 0;
418
419out_sysfs:
420 iommu_device_sysfs_remove(&zdev->iommu_dev);
421
422out_err:
423 return rc;
424}
425
426void zpci_destroy_iommu(struct zpci_dev *zdev)
427{
428 iommu_device_unregister(&zdev->iommu_dev);
429 iommu_device_sysfs_remove(&zdev->iommu_dev);
430}
431
432static const struct iommu_ops s390_iommu_ops = {
433 .capable = s390_iommu_capable,
434 .domain_alloc = s390_domain_alloc,
435 .probe_device = s390_iommu_probe_device,
436 .release_device = s390_iommu_release_device,
437 .device_group = generic_device_group,
438 .pgsize_bitmap = SZ_4K,
439 .get_resv_regions = s390_iommu_get_resv_regions,
440 .default_domain_ops = &(const struct iommu_domain_ops) {
441 .attach_dev = s390_iommu_attach_device,
442 .detach_dev = s390_iommu_detach_device,
443 .map_pages = s390_iommu_map_pages,
444 .unmap_pages = s390_iommu_unmap_pages,
445 .flush_iotlb_all = s390_iommu_flush_iotlb_all,
446 .iotlb_sync = s390_iommu_iotlb_sync,
447 .iotlb_sync_map = s390_iommu_iotlb_sync_map,
448 .iova_to_phys = s390_iommu_iova_to_phys,
449 .free = s390_domain_free,
450 }
451};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * IOMMU API for s390 PCI devices
4 *
5 * Copyright IBM Corp. 2015
6 * Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
7 */
8
9#include <linux/pci.h>
10#include <linux/iommu.h>
11#include <linux/iommu-helper.h>
12#include <linux/sizes.h>
13#include <linux/rculist.h>
14#include <linux/rcupdate.h>
15#include <asm/pci_dma.h>
16
17#include "dma-iommu.h"
18
19static const struct iommu_ops s390_iommu_ops;
20
21static struct kmem_cache *dma_region_table_cache;
22static struct kmem_cache *dma_page_table_cache;
23
24static u64 s390_iommu_aperture;
25static u32 s390_iommu_aperture_factor = 1;
26
27struct s390_domain {
28 struct iommu_domain domain;
29 struct list_head devices;
30 struct zpci_iommu_ctrs ctrs;
31 unsigned long *dma_table;
32 spinlock_t list_lock;
33 struct rcu_head rcu;
34};
35
36static inline unsigned int calc_rtx(dma_addr_t ptr)
37{
38 return ((unsigned long)ptr >> ZPCI_RT_SHIFT) & ZPCI_INDEX_MASK;
39}
40
41static inline unsigned int calc_sx(dma_addr_t ptr)
42{
43 return ((unsigned long)ptr >> ZPCI_ST_SHIFT) & ZPCI_INDEX_MASK;
44}
45
46static inline unsigned int calc_px(dma_addr_t ptr)
47{
48 return ((unsigned long)ptr >> PAGE_SHIFT) & ZPCI_PT_MASK;
49}
50
51static inline void set_pt_pfaa(unsigned long *entry, phys_addr_t pfaa)
52{
53 *entry &= ZPCI_PTE_FLAG_MASK;
54 *entry |= (pfaa & ZPCI_PTE_ADDR_MASK);
55}
56
57static inline void set_rt_sto(unsigned long *entry, phys_addr_t sto)
58{
59 *entry &= ZPCI_RTE_FLAG_MASK;
60 *entry |= (sto & ZPCI_RTE_ADDR_MASK);
61 *entry |= ZPCI_TABLE_TYPE_RTX;
62}
63
64static inline void set_st_pto(unsigned long *entry, phys_addr_t pto)
65{
66 *entry &= ZPCI_STE_FLAG_MASK;
67 *entry |= (pto & ZPCI_STE_ADDR_MASK);
68 *entry |= ZPCI_TABLE_TYPE_SX;
69}
70
71static inline void validate_rt_entry(unsigned long *entry)
72{
73 *entry &= ~ZPCI_TABLE_VALID_MASK;
74 *entry &= ~ZPCI_TABLE_OFFSET_MASK;
75 *entry |= ZPCI_TABLE_VALID;
76 *entry |= ZPCI_TABLE_LEN_RTX;
77}
78
79static inline void validate_st_entry(unsigned long *entry)
80{
81 *entry &= ~ZPCI_TABLE_VALID_MASK;
82 *entry |= ZPCI_TABLE_VALID;
83}
84
85static inline void invalidate_pt_entry(unsigned long *entry)
86{
87 WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_INVALID);
88 *entry &= ~ZPCI_PTE_VALID_MASK;
89 *entry |= ZPCI_PTE_INVALID;
90}
91
92static inline void validate_pt_entry(unsigned long *entry)
93{
94 WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID);
95 *entry &= ~ZPCI_PTE_VALID_MASK;
96 *entry |= ZPCI_PTE_VALID;
97}
98
99static inline void entry_set_protected(unsigned long *entry)
100{
101 *entry &= ~ZPCI_TABLE_PROT_MASK;
102 *entry |= ZPCI_TABLE_PROTECTED;
103}
104
105static inline void entry_clr_protected(unsigned long *entry)
106{
107 *entry &= ~ZPCI_TABLE_PROT_MASK;
108 *entry |= ZPCI_TABLE_UNPROTECTED;
109}
110
111static inline int reg_entry_isvalid(unsigned long entry)
112{
113 return (entry & ZPCI_TABLE_VALID_MASK) == ZPCI_TABLE_VALID;
114}
115
116static inline int pt_entry_isvalid(unsigned long entry)
117{
118 return (entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID;
119}
120
121static inline unsigned long *get_rt_sto(unsigned long entry)
122{
123 if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
124 return phys_to_virt(entry & ZPCI_RTE_ADDR_MASK);
125 else
126 return NULL;
127}
128
129static inline unsigned long *get_st_pto(unsigned long entry)
130{
131 if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
132 return phys_to_virt(entry & ZPCI_STE_ADDR_MASK);
133 else
134 return NULL;
135}
136
137static int __init dma_alloc_cpu_table_caches(void)
138{
139 dma_region_table_cache = kmem_cache_create("PCI_DMA_region_tables",
140 ZPCI_TABLE_SIZE,
141 ZPCI_TABLE_ALIGN,
142 0, NULL);
143 if (!dma_region_table_cache)
144 return -ENOMEM;
145
146 dma_page_table_cache = kmem_cache_create("PCI_DMA_page_tables",
147 ZPCI_PT_SIZE,
148 ZPCI_PT_ALIGN,
149 0, NULL);
150 if (!dma_page_table_cache) {
151 kmem_cache_destroy(dma_region_table_cache);
152 return -ENOMEM;
153 }
154 return 0;
155}
156
157static unsigned long *dma_alloc_cpu_table(gfp_t gfp)
158{
159 unsigned long *table, *entry;
160
161 table = kmem_cache_alloc(dma_region_table_cache, gfp);
162 if (!table)
163 return NULL;
164
165 for (entry = table; entry < table + ZPCI_TABLE_ENTRIES; entry++)
166 *entry = ZPCI_TABLE_INVALID;
167 return table;
168}
169
170static void dma_free_cpu_table(void *table)
171{
172 kmem_cache_free(dma_region_table_cache, table);
173}
174
175static void dma_free_page_table(void *table)
176{
177 kmem_cache_free(dma_page_table_cache, table);
178}
179
180static void dma_free_seg_table(unsigned long entry)
181{
182 unsigned long *sto = get_rt_sto(entry);
183 int sx;
184
185 for (sx = 0; sx < ZPCI_TABLE_ENTRIES; sx++)
186 if (reg_entry_isvalid(sto[sx]))
187 dma_free_page_table(get_st_pto(sto[sx]));
188
189 dma_free_cpu_table(sto);
190}
191
192static void dma_cleanup_tables(unsigned long *table)
193{
194 int rtx;
195
196 if (!table)
197 return;
198
199 for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
200 if (reg_entry_isvalid(table[rtx]))
201 dma_free_seg_table(table[rtx]);
202
203 dma_free_cpu_table(table);
204}
205
206static unsigned long *dma_alloc_page_table(gfp_t gfp)
207{
208 unsigned long *table, *entry;
209
210 table = kmem_cache_alloc(dma_page_table_cache, gfp);
211 if (!table)
212 return NULL;
213
214 for (entry = table; entry < table + ZPCI_PT_ENTRIES; entry++)
215 *entry = ZPCI_PTE_INVALID;
216 return table;
217}
218
219static unsigned long *dma_get_seg_table_origin(unsigned long *rtep, gfp_t gfp)
220{
221 unsigned long old_rte, rte;
222 unsigned long *sto;
223
224 rte = READ_ONCE(*rtep);
225 if (reg_entry_isvalid(rte)) {
226 sto = get_rt_sto(rte);
227 } else {
228 sto = dma_alloc_cpu_table(gfp);
229 if (!sto)
230 return NULL;
231
232 set_rt_sto(&rte, virt_to_phys(sto));
233 validate_rt_entry(&rte);
234 entry_clr_protected(&rte);
235
236 old_rte = cmpxchg(rtep, ZPCI_TABLE_INVALID, rte);
237 if (old_rte != ZPCI_TABLE_INVALID) {
238 /* Somone else was faster, use theirs */
239 dma_free_cpu_table(sto);
240 sto = get_rt_sto(old_rte);
241 }
242 }
243 return sto;
244}
245
246static unsigned long *dma_get_page_table_origin(unsigned long *step, gfp_t gfp)
247{
248 unsigned long old_ste, ste;
249 unsigned long *pto;
250
251 ste = READ_ONCE(*step);
252 if (reg_entry_isvalid(ste)) {
253 pto = get_st_pto(ste);
254 } else {
255 pto = dma_alloc_page_table(gfp);
256 if (!pto)
257 return NULL;
258 set_st_pto(&ste, virt_to_phys(pto));
259 validate_st_entry(&ste);
260 entry_clr_protected(&ste);
261
262 old_ste = cmpxchg(step, ZPCI_TABLE_INVALID, ste);
263 if (old_ste != ZPCI_TABLE_INVALID) {
264 /* Somone else was faster, use theirs */
265 dma_free_page_table(pto);
266 pto = get_st_pto(old_ste);
267 }
268 }
269 return pto;
270}
271
272static unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr, gfp_t gfp)
273{
274 unsigned long *sto, *pto;
275 unsigned int rtx, sx, px;
276
277 rtx = calc_rtx(dma_addr);
278 sto = dma_get_seg_table_origin(&rto[rtx], gfp);
279 if (!sto)
280 return NULL;
281
282 sx = calc_sx(dma_addr);
283 pto = dma_get_page_table_origin(&sto[sx], gfp);
284 if (!pto)
285 return NULL;
286
287 px = calc_px(dma_addr);
288 return &pto[px];
289}
290
291static void dma_update_cpu_trans(unsigned long *ptep, phys_addr_t page_addr, int flags)
292{
293 unsigned long pte;
294
295 pte = READ_ONCE(*ptep);
296 if (flags & ZPCI_PTE_INVALID) {
297 invalidate_pt_entry(&pte);
298 } else {
299 set_pt_pfaa(&pte, page_addr);
300 validate_pt_entry(&pte);
301 }
302
303 if (flags & ZPCI_TABLE_PROTECTED)
304 entry_set_protected(&pte);
305 else
306 entry_clr_protected(&pte);
307
308 xchg(ptep, pte);
309}
310
311static struct s390_domain *to_s390_domain(struct iommu_domain *dom)
312{
313 return container_of(dom, struct s390_domain, domain);
314}
315
316static bool s390_iommu_capable(struct device *dev, enum iommu_cap cap)
317{
318 struct zpci_dev *zdev = to_zpci_dev(dev);
319
320 switch (cap) {
321 case IOMMU_CAP_CACHE_COHERENCY:
322 return true;
323 case IOMMU_CAP_DEFERRED_FLUSH:
324 return zdev->pft != PCI_FUNC_TYPE_ISM;
325 default:
326 return false;
327 }
328}
329
330static struct iommu_domain *s390_domain_alloc_paging(struct device *dev)
331{
332 struct s390_domain *s390_domain;
333
334 s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
335 if (!s390_domain)
336 return NULL;
337
338 s390_domain->dma_table = dma_alloc_cpu_table(GFP_KERNEL);
339 if (!s390_domain->dma_table) {
340 kfree(s390_domain);
341 return NULL;
342 }
343 s390_domain->domain.geometry.force_aperture = true;
344 s390_domain->domain.geometry.aperture_start = 0;
345 s390_domain->domain.geometry.aperture_end = ZPCI_TABLE_SIZE_RT - 1;
346
347 spin_lock_init(&s390_domain->list_lock);
348 INIT_LIST_HEAD_RCU(&s390_domain->devices);
349
350 return &s390_domain->domain;
351}
352
353static void s390_iommu_rcu_free_domain(struct rcu_head *head)
354{
355 struct s390_domain *s390_domain = container_of(head, struct s390_domain, rcu);
356
357 dma_cleanup_tables(s390_domain->dma_table);
358 kfree(s390_domain);
359}
360
361static void s390_domain_free(struct iommu_domain *domain)
362{
363 struct s390_domain *s390_domain = to_s390_domain(domain);
364
365 rcu_read_lock();
366 WARN_ON(!list_empty(&s390_domain->devices));
367 rcu_read_unlock();
368
369 call_rcu(&s390_domain->rcu, s390_iommu_rcu_free_domain);
370}
371
372static void s390_iommu_detach_device(struct iommu_domain *domain,
373 struct device *dev)
374{
375 struct s390_domain *s390_domain = to_s390_domain(domain);
376 struct zpci_dev *zdev = to_zpci_dev(dev);
377 unsigned long flags;
378
379 spin_lock_irqsave(&s390_domain->list_lock, flags);
380 list_del_rcu(&zdev->iommu_list);
381 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
382
383 zpci_unregister_ioat(zdev, 0);
384 zdev->s390_domain = NULL;
385 zdev->dma_table = NULL;
386}
387
388static int s390_iommu_attach_device(struct iommu_domain *domain,
389 struct device *dev)
390{
391 struct s390_domain *s390_domain = to_s390_domain(domain);
392 struct zpci_dev *zdev = to_zpci_dev(dev);
393 unsigned long flags;
394 u8 status;
395 int cc;
396
397 if (!zdev)
398 return -ENODEV;
399
400 if (WARN_ON(domain->geometry.aperture_start > zdev->end_dma ||
401 domain->geometry.aperture_end < zdev->start_dma))
402 return -EINVAL;
403
404 if (zdev->s390_domain)
405 s390_iommu_detach_device(&zdev->s390_domain->domain, dev);
406
407 cc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
408 virt_to_phys(s390_domain->dma_table), &status);
409 /*
410 * If the device is undergoing error recovery the reset code
411 * will re-establish the new domain.
412 */
413 if (cc && status != ZPCI_PCI_ST_FUNC_NOT_AVAIL)
414 return -EIO;
415
416 zdev->dma_table = s390_domain->dma_table;
417 zdev->s390_domain = s390_domain;
418
419 spin_lock_irqsave(&s390_domain->list_lock, flags);
420 list_add_rcu(&zdev->iommu_list, &s390_domain->devices);
421 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
422
423 return 0;
424}
425
426static void s390_iommu_get_resv_regions(struct device *dev,
427 struct list_head *list)
428{
429 struct zpci_dev *zdev = to_zpci_dev(dev);
430 struct iommu_resv_region *region;
431
432 if (zdev->start_dma) {
433 region = iommu_alloc_resv_region(0, zdev->start_dma, 0,
434 IOMMU_RESV_RESERVED, GFP_KERNEL);
435 if (!region)
436 return;
437 list_add_tail(®ion->list, list);
438 }
439
440 if (zdev->end_dma < ZPCI_TABLE_SIZE_RT - 1) {
441 region = iommu_alloc_resv_region(zdev->end_dma + 1,
442 ZPCI_TABLE_SIZE_RT - zdev->end_dma - 1,
443 0, IOMMU_RESV_RESERVED, GFP_KERNEL);
444 if (!region)
445 return;
446 list_add_tail(®ion->list, list);
447 }
448}
449
450static struct iommu_device *s390_iommu_probe_device(struct device *dev)
451{
452 struct zpci_dev *zdev;
453
454 if (!dev_is_pci(dev))
455 return ERR_PTR(-ENODEV);
456
457 zdev = to_zpci_dev(dev);
458
459 if (zdev->start_dma > zdev->end_dma ||
460 zdev->start_dma > ZPCI_TABLE_SIZE_RT - 1)
461 return ERR_PTR(-EINVAL);
462
463 if (zdev->end_dma > ZPCI_TABLE_SIZE_RT - 1)
464 zdev->end_dma = ZPCI_TABLE_SIZE_RT - 1;
465
466 if (zdev->tlb_refresh)
467 dev->iommu->shadow_on_flush = 1;
468
469 return &zdev->iommu_dev;
470}
471
472static void s390_iommu_release_device(struct device *dev)
473{
474 struct zpci_dev *zdev = to_zpci_dev(dev);
475
476 /*
477 * release_device is expected to detach any domain currently attached
478 * to the device, but keep it attached to other devices in the group.
479 */
480 if (zdev)
481 s390_iommu_detach_device(&zdev->s390_domain->domain, dev);
482}
483
484static int zpci_refresh_all(struct zpci_dev *zdev)
485{
486 return zpci_refresh_trans((u64)zdev->fh << 32, zdev->start_dma,
487 zdev->end_dma - zdev->start_dma + 1);
488}
489
490static void s390_iommu_flush_iotlb_all(struct iommu_domain *domain)
491{
492 struct s390_domain *s390_domain = to_s390_domain(domain);
493 struct zpci_dev *zdev;
494
495 rcu_read_lock();
496 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
497 atomic64_inc(&s390_domain->ctrs.global_rpcits);
498 zpci_refresh_all(zdev);
499 }
500 rcu_read_unlock();
501}
502
503static void s390_iommu_iotlb_sync(struct iommu_domain *domain,
504 struct iommu_iotlb_gather *gather)
505{
506 struct s390_domain *s390_domain = to_s390_domain(domain);
507 size_t size = gather->end - gather->start + 1;
508 struct zpci_dev *zdev;
509
510 /* If gather was never added to there is nothing to flush */
511 if (!gather->end)
512 return;
513
514 rcu_read_lock();
515 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
516 atomic64_inc(&s390_domain->ctrs.sync_rpcits);
517 zpci_refresh_trans((u64)zdev->fh << 32, gather->start,
518 size);
519 }
520 rcu_read_unlock();
521}
522
523static int s390_iommu_iotlb_sync_map(struct iommu_domain *domain,
524 unsigned long iova, size_t size)
525{
526 struct s390_domain *s390_domain = to_s390_domain(domain);
527 struct zpci_dev *zdev;
528 int ret = 0;
529
530 rcu_read_lock();
531 list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
532 if (!zdev->tlb_refresh)
533 continue;
534 atomic64_inc(&s390_domain->ctrs.sync_map_rpcits);
535 ret = zpci_refresh_trans((u64)zdev->fh << 32,
536 iova, size);
537 /*
538 * let the hypervisor discover invalidated entries
539 * allowing it to free IOVAs and unpin pages
540 */
541 if (ret == -ENOMEM) {
542 ret = zpci_refresh_all(zdev);
543 if (ret)
544 break;
545 }
546 }
547 rcu_read_unlock();
548
549 return ret;
550}
551
552static int s390_iommu_validate_trans(struct s390_domain *s390_domain,
553 phys_addr_t pa, dma_addr_t dma_addr,
554 unsigned long nr_pages, int flags,
555 gfp_t gfp)
556{
557 phys_addr_t page_addr = pa & PAGE_MASK;
558 unsigned long *entry;
559 unsigned long i;
560 int rc;
561
562 for (i = 0; i < nr_pages; i++) {
563 entry = dma_walk_cpu_trans(s390_domain->dma_table, dma_addr,
564 gfp);
565 if (unlikely(!entry)) {
566 rc = -ENOMEM;
567 goto undo_cpu_trans;
568 }
569 dma_update_cpu_trans(entry, page_addr, flags);
570 page_addr += PAGE_SIZE;
571 dma_addr += PAGE_SIZE;
572 }
573
574 return 0;
575
576undo_cpu_trans:
577 while (i-- > 0) {
578 dma_addr -= PAGE_SIZE;
579 entry = dma_walk_cpu_trans(s390_domain->dma_table,
580 dma_addr, gfp);
581 if (!entry)
582 break;
583 dma_update_cpu_trans(entry, 0, ZPCI_PTE_INVALID);
584 }
585
586 return rc;
587}
588
589static int s390_iommu_invalidate_trans(struct s390_domain *s390_domain,
590 dma_addr_t dma_addr, unsigned long nr_pages)
591{
592 unsigned long *entry;
593 unsigned long i;
594 int rc = 0;
595
596 for (i = 0; i < nr_pages; i++) {
597 entry = dma_walk_cpu_trans(s390_domain->dma_table, dma_addr,
598 GFP_ATOMIC);
599 if (unlikely(!entry)) {
600 rc = -EINVAL;
601 break;
602 }
603 dma_update_cpu_trans(entry, 0, ZPCI_PTE_INVALID);
604 dma_addr += PAGE_SIZE;
605 }
606
607 return rc;
608}
609
610static int s390_iommu_map_pages(struct iommu_domain *domain,
611 unsigned long iova, phys_addr_t paddr,
612 size_t pgsize, size_t pgcount,
613 int prot, gfp_t gfp, size_t *mapped)
614{
615 struct s390_domain *s390_domain = to_s390_domain(domain);
616 size_t size = pgcount << __ffs(pgsize);
617 int flags = ZPCI_PTE_VALID, rc = 0;
618
619 if (pgsize != SZ_4K)
620 return -EINVAL;
621
622 if (iova < s390_domain->domain.geometry.aperture_start ||
623 (iova + size - 1) > s390_domain->domain.geometry.aperture_end)
624 return -EINVAL;
625
626 if (!IS_ALIGNED(iova | paddr, pgsize))
627 return -EINVAL;
628
629 if (!(prot & IOMMU_WRITE))
630 flags |= ZPCI_TABLE_PROTECTED;
631
632 rc = s390_iommu_validate_trans(s390_domain, paddr, iova,
633 pgcount, flags, gfp);
634 if (!rc) {
635 *mapped = size;
636 atomic64_add(pgcount, &s390_domain->ctrs.mapped_pages);
637 }
638
639 return rc;
640}
641
642static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
643 dma_addr_t iova)
644{
645 struct s390_domain *s390_domain = to_s390_domain(domain);
646 unsigned long *rto, *sto, *pto;
647 unsigned long ste, pte, rte;
648 unsigned int rtx, sx, px;
649 phys_addr_t phys = 0;
650
651 if (iova < domain->geometry.aperture_start ||
652 iova > domain->geometry.aperture_end)
653 return 0;
654
655 rtx = calc_rtx(iova);
656 sx = calc_sx(iova);
657 px = calc_px(iova);
658 rto = s390_domain->dma_table;
659
660 rte = READ_ONCE(rto[rtx]);
661 if (reg_entry_isvalid(rte)) {
662 sto = get_rt_sto(rte);
663 ste = READ_ONCE(sto[sx]);
664 if (reg_entry_isvalid(ste)) {
665 pto = get_st_pto(ste);
666 pte = READ_ONCE(pto[px]);
667 if (pt_entry_isvalid(pte))
668 phys = pte & ZPCI_PTE_ADDR_MASK;
669 }
670 }
671
672 return phys;
673}
674
675static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
676 unsigned long iova,
677 size_t pgsize, size_t pgcount,
678 struct iommu_iotlb_gather *gather)
679{
680 struct s390_domain *s390_domain = to_s390_domain(domain);
681 size_t size = pgcount << __ffs(pgsize);
682 int rc;
683
684 if (WARN_ON(iova < s390_domain->domain.geometry.aperture_start ||
685 (iova + size - 1) > s390_domain->domain.geometry.aperture_end))
686 return 0;
687
688 rc = s390_iommu_invalidate_trans(s390_domain, iova, pgcount);
689 if (rc)
690 return 0;
691
692 iommu_iotlb_gather_add_range(gather, iova, size);
693 atomic64_add(pgcount, &s390_domain->ctrs.unmapped_pages);
694
695 return size;
696}
697
698static void s390_iommu_probe_finalize(struct device *dev)
699{
700 iommu_setup_dma_ops(dev, 0, U64_MAX);
701}
702
703struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev)
704{
705 if (!zdev || !zdev->s390_domain)
706 return NULL;
707 return &zdev->s390_domain->ctrs;
708}
709
710int zpci_init_iommu(struct zpci_dev *zdev)
711{
712 u64 aperture_size;
713 int rc = 0;
714
715 rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL,
716 "s390-iommu.%08x", zdev->fid);
717 if (rc)
718 goto out_err;
719
720 rc = iommu_device_register(&zdev->iommu_dev, &s390_iommu_ops, NULL);
721 if (rc)
722 goto out_sysfs;
723
724 zdev->start_dma = PAGE_ALIGN(zdev->start_dma);
725 aperture_size = min3(s390_iommu_aperture,
726 ZPCI_TABLE_SIZE_RT - zdev->start_dma,
727 zdev->end_dma - zdev->start_dma + 1);
728 zdev->end_dma = zdev->start_dma + aperture_size - 1;
729
730 return 0;
731
732out_sysfs:
733 iommu_device_sysfs_remove(&zdev->iommu_dev);
734
735out_err:
736 return rc;
737}
738
739void zpci_destroy_iommu(struct zpci_dev *zdev)
740{
741 iommu_device_unregister(&zdev->iommu_dev);
742 iommu_device_sysfs_remove(&zdev->iommu_dev);
743}
744
745static int __init s390_iommu_setup(char *str)
746{
747 if (!strcmp(str, "strict")) {
748 pr_warn("s390_iommu=strict deprecated; use iommu.strict=1 instead\n");
749 iommu_set_dma_strict();
750 }
751 return 1;
752}
753
754__setup("s390_iommu=", s390_iommu_setup);
755
756static int __init s390_iommu_aperture_setup(char *str)
757{
758 if (kstrtou32(str, 10, &s390_iommu_aperture_factor))
759 s390_iommu_aperture_factor = 1;
760 return 1;
761}
762
763__setup("s390_iommu_aperture=", s390_iommu_aperture_setup);
764
765static int __init s390_iommu_init(void)
766{
767 int rc;
768
769 iommu_dma_forcedac = true;
770 s390_iommu_aperture = (u64)virt_to_phys(high_memory);
771 if (!s390_iommu_aperture_factor)
772 s390_iommu_aperture = ULONG_MAX;
773 else
774 s390_iommu_aperture *= s390_iommu_aperture_factor;
775
776 rc = dma_alloc_cpu_table_caches();
777 if (rc)
778 return rc;
779
780 return rc;
781}
782subsys_initcall(s390_iommu_init);
783
784static const struct iommu_ops s390_iommu_ops = {
785 .capable = s390_iommu_capable,
786 .domain_alloc_paging = s390_domain_alloc_paging,
787 .probe_device = s390_iommu_probe_device,
788 .probe_finalize = s390_iommu_probe_finalize,
789 .release_device = s390_iommu_release_device,
790 .device_group = generic_device_group,
791 .pgsize_bitmap = SZ_4K,
792 .get_resv_regions = s390_iommu_get_resv_regions,
793 .default_domain_ops = &(const struct iommu_domain_ops) {
794 .attach_dev = s390_iommu_attach_device,
795 .map_pages = s390_iommu_map_pages,
796 .unmap_pages = s390_iommu_unmap_pages,
797 .flush_iotlb_all = s390_iommu_flush_iotlb_all,
798 .iotlb_sync = s390_iommu_iotlb_sync,
799 .iotlb_sync_map = s390_iommu_iotlb_sync_map,
800 .iova_to_phys = s390_iommu_iova_to_phys,
801 .free = s390_domain_free,
802 }
803};